Navy IT helps find shipwrecks

Mine-hunting technology may enable marine archaeologists to see below the seafloor

By Kathleen Hickey

May 21, 2008

The Navy, in conjunction with the National Oceanic and Atmospheric Administration, is testing mine-hunting technology as an aid to marine archaeological research.

Mine-hunting technology has the potential to help NOAA find historic shipwrecks by letting maritime archaeologists see below the seafloor and provide better images than previous technology. Acoustic sonar can scan broad areas of the seafloor and provide fine-detail images of objects, and below-bottom imaging systems can generate tomographic, or sectional, images of buried objects.

The technology will be used to survey four shipwrecks, including the HMS Cerberus, a 28-gun British frigate intentionally sunk along with other ships in 1778 to avoid capture by an approaching French fleet.

Testing of 13 autonomous underwater vehicles (AUVs) equipped with mine-hunting sensors took place in Narragansett Bay at the Naval Undersea Warfare Center in Newport, R.I. The event was co-sponsored by the Office of Naval Research and NOAA's Office of Ocean Exploration and Research.

AUVs are computer-controlled systems operating underwater. They have no physical connection to their operator, who may be onshore or aboard a ship. They are also self-guiding and self-powered. Unlike remotely operated vehicles ' where the operator uses a joystick to control the system ' the operator is not driving the vehicle. The operator can, however, exchange messages with the system.

The vehicles can function in shallower water than boats and deeper water than human divers or tethered vehicles. Once deployed and underwater, they are safe from bad weather. They are also configurable: Scientists can choose which sensors to attach depending on their research objectives. Furthermore, they are much less expensive than research vessels and can complete identical repeat surveys of an area.

The vehicles can glide from sea surface to the depths and back. Others can stop, hover, and move the way blimps or helicopters do through the air. Solar-powered AUVs can spend a portion of their time at the surface. They can be small and easily portable or very large, weighing thousands of pounds.

In addition to marine archeology, the technology was also tested last week to search for, classify and neutralize sea mines. Since World War II, more U.S. Navy ships have been damaged or lost due to mines than to all other causes combined.

'Historically, maritime archaeologists have not had access to as much advanced technology as we would like,' said Frank Cantelas, a maritime archaeologist at NOAA's Office of Ocean Exploration and Research. 'By introducing maritime archaeologists to this new technology, NOAA hopes to significantly advance and support how archaeologists will search for sunken history.'